Laravel源码分析--Laravel生命周期详解

<?php

/**
 * Laravel - A PHP Framework For Web Artisans
 *
 * @package  Laravel
 * @author   Taylor Otwell <taylor@laravel.com>
 */

define('LARAVEL_START', microtime(true));

/*
|--------------------------------------------------------------------------
| Register The Auto Loader
|--------------------------------------------------------------------------
|
| Composer provides a convenient, automatically generated class loader for
| our application. We just need to utilize it! We'll simply require it
| into the script here so that we don't have to worry about manual
| loading any of our classes later on. It feels great to relax.
|
*/

require __DIR__.'/../vendor/autoload.php';

/*
|--------------------------------------------------------------------------
| Turn On The Lights
|--------------------------------------------------------------------------
|
| We need to illuminate PHP development, so let us turn on the lights.
| This bootstraps the framework and gets it ready for use, then it
| will load up this application so that we can run it and send
| the responses back to the browser and delight our users.
|
*/

$app = require_once __DIR__.'/../bootstrap/app.php';

/*
|--------------------------------------------------------------------------
| Run The Application
|--------------------------------------------------------------------------
|
| Once we have the application, we can handle the incoming request
| through the kernel, and send the associated response back to
| the client's browser allowing them to enjoy the creative
| and wonderful application we have prepared for them.
|
*/

$kernel = $app->make(Illuminate\Contracts\Http\Kernel::class);

$response = $kernel->handle(
    $request = Illuminate\Http\Request::capture()
);

$response->send();

$kernel->terminate($request, $response);

    public function findFile($class)
    {
        // class map lookup
        if (isset($this->classMap[$class])) {
            return $this->classMap[$class];
        }
        if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
            return false;
        }
        if (null !== $this->apcuPrefix) {
            $file = apcu_fetch($this->apcuPrefix.$class, $hit);
            if ($hit) {
                return $file;
            }
        }

        $file = $this->findFileWithExtension($class, '.php');

        // Search for Hack files if we are running on HHVM
        if (false === $file && defined('HHVM_VERSION')) {
            $file = $this->findFileWithExtension($class, '.hh');
        }

        if (null !== $this->apcuPrefix) {
            apcu_add($this->apcuPrefix.$class, $file);
        }

        if (false === $file) {
            // Remember that this class does not exist.
            $this->missingClasses[$class] = true;
        }

        return $file;
    }

<?php/*
|--------------------------------------------------------------------------
| Create The Application
|--------------------------------------------------------------------------
|
| The first thing we will do is create a new Laravel application instance
| which serves as the "glue" for all the components of Laravel, and is
| the IoC container for the system binding all of the various parts.
|
*/

$app = new Illuminate\Foundation\Application(
    realpath(__DIR__.'/../')
);

/*
|--------------------------------------------------------------------------
| Bind Important Interfaces
|--------------------------------------------------------------------------
|
| Next, we need to bind some important interfaces into the container so
| we will be able to resolve them when needed. The kernels serve the
| incoming requests to this application from both the web and CLI.
|
*/

$app->singleton(
    Illuminate\Contracts\Http\Kernel::class,
    App\Http\Kernel::class
);

$app->singleton(
    Illuminate\Contracts\Console\Kernel::class,
    App\Console\Kernel::class
);

$app->singleton(
    Illuminate\Contracts\Debug\ExceptionHandler::class,
    App\Exceptions\Handler::class
);

/*
|--------------------------------------------------------------------------
| Return The Application
|--------------------------------------------------------------------------
|
| This script returns the application instance. The instance is given to
| the calling script so we can separate the building of the instances
| from the actual running of the application and sending responses.
|
*/

return $app;

public function __construct($basePath = null)
    {
        if ($basePath) {
            $this->setBasePath($basePath);
        }

        $this->registerBaseBindings();

        $this->registerBaseServiceProviders();

        $this->registerCoreContainerAliases();
    }

protected function bindPathsInContainer()
    {
        $this->instance('path', $this->path());
        $this->instance('path.base', $this->basePath());
        $this->instance('path.lang', $this->langPath());
        $this->instance('path.config', $this->configPath());
        $this->instance('path.public', $this->publicPath());
        $this->instance('path.storage', $this->storagePath());
        $this->instance('path.database', $this->databasePath());
        $this->instance('path.resources', $this->resourcePath());
        $this->instance('path.bootstrap', $this->bootstrapPath());
    }

protected function registerBaseBindings()
    {
        static::setInstance($this);

        $this->instance('app', $this);

        $this->instance(Container::class, $this);

        $this->instance(PackageManifest::class, new PackageManifest(
            new Filesystem, $this->basePath(), $this->getCachedPackagesPath()
        ));
    }

　　 protected function registerBaseServiceProviders()
    {
        $this->register(new EventServiceProvider($this));

        $this->register(new LogServiceProvider($this));

        $this->register(new RoutingServiceProvider($this));
    }

　　  /**
     * Handle an incoming HTTP request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function handle($request)
    {
        try {
            $request->enableHttpMethodParameterOverride();

            $response = $this->sendRequestThroughRouter($request);
        } catch (Exception $e) {
            $this->reportException($e);

            $response = $this->renderException($request, $e);
        } catch (Throwable $e) {
            $this->reportException($e = new FatalThrowableError($e));

            $response = $this->renderException($request, $e);
        }

        $this->app['events']->dispatch(
            new Events\RequestHandled($request, $response)
        );

        return $response;
    }

    /**
     * Send the given request through the middleware / router.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    protected function sendRequestThroughRouter($request)
    {
        $this->app->instance('request', $request);

        Facade::clearResolvedInstance('request');

        $this->bootstrap();

        return (new Pipeline($this->app))
                    ->send($request)
                    ->through($this->app->shouldSkipMiddleware() ? [] : $this->middleware)
                    ->then($this->dispatchToRouter());
    }

protected $bootstrappers = [
        \Illuminate\Foundation\Bootstrap\LoadEnvironmentVariables::class,
        \Illuminate\Foundation\Bootstrap\LoadConfiguration::class,
        \Illuminate\Foundation\Bootstrap\HandleExceptions::class,
        \Illuminate\Foundation\Bootstrap\RegisterFacades::class,
        \Illuminate\Foundation\Bootstrap\RegisterProviders::class,
        \Illuminate\Foundation\Bootstrap\BootProviders::class,
    ];

public function bootstrapWith(array $bootstrappers)
    {
        $this->hasBeenBootstrapped = true;

        foreach ($bootstrappers as $bootstrapper) {
            $this['events']->fire('bootstrapping: '.$bootstrapper, [$this]);

            $this->make($bootstrapper)->bootstrap($this);

            $this['events']->fire('bootstrapped: '.$bootstrapper, [$this]);
        }
    }

return (new Pipeline($this->app))
                    ->send($request)  // 设置需要分发的request
                    ->through($this->app->shouldSkipMiddleware() ? [] : $this->middleware)　　// 设置request需要通过的中间件
                    ->then($this->dispatchToRouter());　　// 开始通过中间件

    /**
     * Run the pipeline with a final destination callback.
     *
     * @param  \Closure  $destination
     * @return mixed
     */
    public function then(Closure $destination)
    {
        $pipeline = array_reduce(
            array_reverse($this->pipes), $this->carry(), $this->prepareDestination($destination)
        );

        return $pipeline($this->passable);
    }

    protected function carry()
    {
        return function ($stack, $pipe) {
            return function ($passable) use ($stack, $pipe) {
                if (is_callable($pipe)) {
                    // If the pipe is an instance of a Closure, we will just call it directly but
                    // otherwise we'll resolve the pipes out of the container and call it with
                    // the appropriate method and arguments, returning the results back out.
                    return $pipe($passable, $stack);
                } elseif (! is_object($pipe)) {
　　　　　　　　　　　　// $pipe是中间件的类名所以会进入这里，parsePipeString方法是解析中间件有没有携带参数，如果没有则$parameters是一个空数组。
                    list($name, $parameters) = $this->parsePipeString($pipe);

                    // If the pipe is a string we will parse the string and resolve the class out
                    // of the dependency injection container. We can then build a callable and
                    // execute the pipe function giving in the parameters that are required.
                    $pipe = $this->getContainer()->make($name);　　　　// 从容器中解析出中间件类
　　　　　　　　　　　　
　　　　　　　　　　　　// $passable就是request, $stack就是包洋葱时包进来的闭包　　
                    $parameters = array_merge([$passable, $stack], $parameters);
                } else {
                    // If the pipe is already an object we'll just make a callable and pass it to
                    // the pipe as-is. There is no need to do any extra parsing and formatting
                    // since the object we're given was already a fully instantiated object.
                    $parameters = [$passable, $stack];
                }

　　　　　　　　　　// 如果中间件中有$this->method方法(其实就是handle方法)，则传入$parameters参数，执行handle方法。
                $response = method_exists($pipe, $this->method)
                                ? $pipe->{$this->method}(...$parameters)
                                : $pipe(...$parameters);

                return $response instanceof Responsable
                            ? $response->toResponse($this->container->make(Request::class))
                            : $response;
            };
        };

　　  /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     *
     * @throws \Symfony\Component\HttpKernel\Exception\HttpException
     */
    public function handle($request, Closure $next)
    {
　　　　　// 判断项目是否下线
        if ($this->app->isDownForMaintenance()) {
            $data = json_decode(file_get_contents($this->app->storagePath().'/framework/down'), true);
　　　　　　　// 验证IP白名单
            if (isset($data['allowed']) && IpUtils::checkIp($request->ip(), (array) $data['allowed'])) {
                return $next($request);
            }
　　　　　　　// 验证path是否在 $except 数组中
            if ($this->inExceptArray($request)) {
                return $next($request);
            }

            throw new MaintenanceModeException($data['time'], $data['retry'], $data['message']);
        }
　　　　　// 如果通过，则传request到闭包继续执行
        return $next($request);
    }

　　 /**
     * Get the route dispatcher callback.
     *
     * @return \Closure
     */
    protected function dispatchToRouter()
    {
        return function ($request) {
　　　　　　　// 向容器中放入实例request
            $this->app->instance('request', $request);

　　　　　　　// 通过\Illuminate\Routing\Router的dispatch方法分发request
　　　　　　　return $this->router->dispatch($request); }; 
　　 }